Turntable with stable speed.

Im afraid Omsed is right. Optical speed control is a nice marketing theme but fails to give truly constant speed. It was an error of micro seiki too, continuous speed corrections created exactly the opposite effect of keeping the speed constant. and it is very audible..

as for the high torque, we could discuss the benefits for the low freq reproduction but it surely has nothing to do with pitch stability. unless it is coupled to high friction bearings, and this is not the case. (which would eventually create rumble issues but that's another story)

The Amadeus has better pitch stability than many other belt drives but you would do better to look at a brinkman Bardo, technics or Garrard IMO.

Get a Technics SL-1200 MK 5 modded by KAB USA and call it a day.

If speed stability is you primary concern, the late 70s DD japanese systems really had that down pat. I bought a Sony PS-x65 for my wife, due to the auto features. I has a composite plinth and a magnetic strip under the platter to measure speed which is then locked with a quartz frequency generator. Based on the strobe, it never fluctuates from dead on, at least for the pretty long time I watched it to see if it did. Even the best belt drives I have watched have some fluctuation, not a lot, and not audible to me, but not rock steady like the Sony. I suspect the other DD of the same vintage are similar. Now, get one of the high end ones for about $500, put on an SME 309 and a Lyra Delos, and you should have an excellent system.

Sorry, I meant "47 Labs" not "RS Labs".
see here